From 911d91c55c6539e32d21db64777d5e5c59b155e5 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Thu, 11 Nov 2021 14:35:51 -0800
Subject: [PATCH] Retry hid_send_feature_report() if the ioctl() fails with
EPIPE (e.g. the device stalled)
---
src/hidapi/linux/hid.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/src/hidapi/linux/hid.c b/src/hidapi/linux/hid.c
index 2c7128f451..5fa2db4ba6 100644
--- a/src/hidapi/linux/hid.c
+++ b/src/hidapi/linux/hid.c
@@ -826,15 +826,23 @@ int HID_API_EXPORT hid_set_nonblocking(hid_device *dev, int nonblock)
return 0; /* Success */
}
-
int HID_API_EXPORT hid_send_feature_report(hid_device *dev, const unsigned char *data, size_t length)
{
+ static const int MAX_RETRIES = 50;
+ int retry;
int res;
- res = ioctl(dev->device_handle, HIDIOCSFEATURE(length), data);
- if (res < 0)
- perror("ioctl (SFEATURE)");
+ for (retry = 0; retry < MAX_RETRIES; ++retry) {
+ res = ioctl(dev->device_handle, HIDIOCSFEATURE(length), data);
+ if (res < 0 && errno == EPIPE) {
+ /* Try again... */
+ continue;
+ }
+ if (res < 0)
+ perror("ioctl (SFEATURE)");
+ break;
+ }
return res;
}